Goblin SharkThis family of sharks is a lineage that goes back 125 million years. Goblin sharks dwell at the bottom of the ocean and rarely stray from there. A live goblin shark was caught in Japan in January 2007 but died within days.
Saltwater crocodilesCrocodiles have been around for more than 200 million years. Saltwater crocodiles normally live for over 70 years. Cassius, the world's largest captive crocodile, is believed to be up to 120 years old.
Seychelles giant tortoiseTortoises are famed for their longevity. These have been inhabiting the Earth for around 17 million years. Today, the oldest living Seychelles giant tortoise is 190 years old Jonathan.
JellyfishThe oldest known jellyfish fossils were found in Utah and date back to 505 million years ago. These are found in all stretches of water from shallow riverbeds to the deep seas. Jellyfish are not fish, despite their name.
Rougheye RockfishFossil evidence suggests that rockfish have been around for tens of millions of years, with some estimates dating back to around five to 10 million years.
Greenland sharkFossil evidence suggests that sharks have been around for at least 200 million years, dating back to the late Triassic period. The Greenland shark itself is thought to have evolved around 60 million years ago.
Black coralAs per fossil evidence, black corals have existed for over 400 million years. Black corals are known for their hard, often black skeletons and can be found in deep-sea habitats as well as in shallow tropical waters.
Horseshoe crabsThese have existed for approximately 450 million years. They first appeared in the Cambrian period, around the time when early marine life was diversifying.
Emperor scorpionsScorpions are believed to have been around for about 250 million years. Emperor scorpions have evolved within the past 50 to 100 million years.
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